(Adds details on mining rate guidance, background)
April 11 (Reuters) - Australia's New Century Resources Ltd NCZ.AX said on Thursday that quarterly zinc production rose 50 percent over the previous quarter following the ramp up of its processing plant performance.
The company churned out 18,170 tonnes of zinc metal in the March quarter, compared with 12,080 tonnes produced in December quarter, it said in a statement to the Australian Stock Exchange.
New Century is processing the tailings, or left over residue, from previously mined ore at the Century mine, once the world's largest zinc mine.
The company said the quality of zinc concentrate produced improved over the period, with lead impurity content dropping 25 percent from the December quarter.
The impact of Australia's wet season and marginally lower grade zones led to an 8 percent fall in overall zinc metal mined to 1.39 million tonnes at 2.92 percent zinc, but the increase in total metal mined reflected the plant's improved metallurgical performance.
The company said it is targeting a mining rate consistently over 8 million tonnes per annum (mtpa) during the June quarter, and a ramp up to 15 mtpa by the end of calendar year 2019.